JP2006264253A - Lens forming method and lens forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens forming method which can form a lens of a desired shape on a substrate surface without increasing a cost and the tact time, and further without lowering lens characteristics. <P>SOLUTION: A first curable light transparent material 19a, which is a lens mold forming material, is coated in a dropping form on a surface of the transparent substrate 11, and after the curing of the material 19a and the formation of a concave-shaped lens mold 19b, a second curable light transparent material 20a which is a lens forming material is filled in a dropping form into the lens mold 19b. By curing the material, a lens 20b of the arbitrary shape where the lens mold 19b is used as a template is formed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lens forming method and a lens forming apparatus. More specifically, the present invention relates to a lens forming method for forming a plurality of minute lenses on a substrate surface, and a lens forming apparatus for carrying out the lens forming method. Is.

  Conventionally, as a technique for forming a microlens on a substrate surface, a mold method and a photolithography method are known.

  However, since the mold method requires a mold, a new mold is required every time the shape or pattern of the lens to be formed is changed, resulting in an increase in cost. Similarly, the photolithography method has a problem that the cost increases because a new mask is required by changing the pattern.

  As a method for solving such a problem, a method of forming a lens on a substrate surface by dropping and adhering a liquid lens forming material onto the substrate surface by an ink jet method and curing the material is proposed (for example, Patent Document 1). . Although this inkjet method has the advantage of not requiring a mold or a mask, the substrate is pretreated (such as cleaning and surface modification) so that the lens forming material forms a lens curvature corresponding to the desired lens shape. ) To increase the tact time.

  Therefore, as a method for easily controlling the lens shape, a resin absorption layer made of a first resin is formed on the substrate surface, and a solution containing a second resin having a refractive index different from that of the first resin is dropped by an inkjet method. A method of forming a lens on the surface of the substrate by allowing it to penetrate into the resin absorption layer (for example, Patent Document 2) has been proposed. However, such a method has a problem in that the lens surface becomes unsmooth due to the resin absorption layer, and the lens characteristics deteriorate.

  In addition, these methods can form a spherical lens because the surface tension of the lens forming material, which is a liquid, is used, but it is not possible to form a short focal aspherical lens without spherical aberration. There is also.

  Furthermore, when a colored lens is formed by these methods, the lens shape is spherical, so that the path length of the light differs depending on the location where the light is incident, and color unevenness occurs due to the difference in the path length. There is a point.

  An object of the present invention is to implement a lens forming method capable of forming a lens of an arbitrary shape on a substrate surface without increasing the cost and tact time and without deteriorating lens characteristics, and to implement the lens forming method An object of the present invention is to provide a lens forming apparatus.

Japanese Patent Laid-Open No. 11-142608 JP-A-11-142611

  According to one aspect of the present invention, a curable translucent first material is applied to the surface of a translucent substrate to form an application portion, and the application portion is cured while controlling the curing conditions, thereby forming a concave shape. There is provided a lens forming method for forming a lens mold by filling the lens mold with a curable translucent second material and curing it.

  Here, as the translucent substrate, for example, a substrate made of plastic such as polycarbonate, polyarylate, polyethylene terephthalate is used in addition to the glass substrate. The curable translucent first material is a material for forming a lens mold (lens mold forming material). For example, a thermosetting resin such as an acrylic resin such as polymethyl methacrylate or an allyl resin such as polycarbonate is used. Ink dispersed in a solvent is used. The curable translucent second material is a material for forming a lens (lens forming material). In addition to these thermosetting resins, for example, an electron beam curable resin such as a radical polymerization type ultraviolet curable resin. Ink dispersed in a solvent is used. The refractive index n1 of the lens mold and the refractive index n2 of the lens are selected so as to satisfy the relationship n1 <n2, for example.

  In order to form the lens mold by curing the application portion formed by applying the first material into a concave shape, for example, the following is performed. That is, the first material is selected from those containing an electron beam curable material or a thermosetting material, and the amount of electron beam irradiation or the amount of heat applied to the central portion of the coating portion formed by applying the first material is set to the outer periphery. The flow rate of the first material in the central portion is maintained larger than that in the outer peripheral portion by making the electron beam irradiation amount or heating amount to the portion smaller, and the first material in the central portion having higher flowability is maintained. , It is moved to the outer peripheral portion where curing by electron beam irradiation or heating is faster, and therefore volume shrinkage also proceeds faster.

  According to another aspect of the present invention, a stage for holding a translucent substrate and a first material supply mechanism for supplying a curable translucent first material for forming a lens mold on the surface of the substrate And a second material supply mechanism for supplying a curable translucent second material for forming a lens on a lens mold formed on the surface of the substrate. Is done.

  According to the lens forming method of the present invention, the second material, which is the lens forming material, is included in the concave lens mold formed of the first material regardless of the type of the substrate on which the lens is formed and the surface state. Filled. That is, the lens can be formed into an arbitrary shape by filling the second material using the concave lens shape formed of the first material as a lens template. Thus, since the shape of the lens is determined by the shape of the lens mold, not only a spherical lens but also an arbitrary aspherical lens can be formed.

  Further, if the lens mold is a convex shape, the lens to be formed may be displaced so that the lens cannot be formed at a predetermined position, resulting in low positional accuracy. According to the lens forming method of the present invention, the lens mold By forming a concave shape, a lens having an arbitrary shape can be accurately formed at a predetermined position without changing any of the first material and the second material.

  Thereby, it is not necessary to change the mold or the photolithography mask by changing the design of the lens, and the cost can be reduced. In addition, it is only necessary to form a lens mold only at a location where a lens is to be formed, and it is not necessary to surface-treat the entire surface of the substrate, thereby preventing an increase in tact time and cost. Furthermore, since the problem of losing the smoothness of the lens surface that occurs when the absorption layer is formed does not occur, there is no possibility that the lens characteristics deteriorate.

  According to the lens forming apparatus according to the present invention, the lens forming method according to the present invention can be carried out reliably and easily.

  In a preferred embodiment of the present invention, at least one of the first material and the second material contains an electron beam curable material, and at least one of the lens mold and the lens has at least one of the first material and the second material as an electron. It is formed by curing by irradiation of a line. According to this lens forming method, a lens template having an arbitrary shape can be formed by controlling the concave shape of the lens mold by changing the irradiation condition of the electron beam. In addition, when forming a colored lens, in the conventional method, color unevenness has occurred due to the difference in the path length of light incident on the lens. It is possible to correct color unevenness caused by the difference between the two, and an excellent colored lens can be formed.

  In a preferred embodiment of the present invention, the lens mold is formed by making the irradiation amount to the outer peripheral portion of the application portion larger than the irradiation amount to the central portion of the application portion. Accordingly, the fluidity of the first material in the central portion of the application portion is maintained larger than that in the outer peripheral portion, and the first material in the central portion having higher fluidity is faster to cure by electron beam irradiation or heating. Volumetric shrinkage can also be moved to the outer periphery where it proceeds faster.

  In a preferred embodiment of the present invention, the electron beam irradiation is performed from a surface opposite to the surface of the substrate on which the coating portion is formed. Thereby, it becomes easy to control the electron beam irradiation amount, and it becomes possible to control the concave shape of the lens mold by creating a specific distribution state of the irradiation amount of the first material.

  In a preferred embodiment of the present invention, at least one of the first material and the second material contains a thermosetting material, and at least one of the lens mold and the lens has at least one of the first material and the second material at a predetermined temperature. It is formed by curing by the above heating. If it does in this way, at least one of the concave shape of a lens type | mold and the shape of a lens can be controlled by changing the heating conditions of at least one of a 1st material and a 2nd material. That is, it is possible to reliably form a lens template having an arbitrary shape and thus a lens without performing a complicated process.

  The lens forming apparatus according to the present invention preferably further includes a horizontal movement mechanism for moving the stage in the horizontal plane and a horizontal rotation mechanism for rotating the stage in the horizontal plane. In this case, it is possible to form a lens at an arbitrary position on the substrate by moving and rotating the stage in a horizontal plane. It is also possible to transport the substrate to the next step.

  In a preferred embodiment of the present invention, the electronic device further includes at least one of an electron beam irradiation mechanism and a heating mechanism for curing at least one of the first material and the second material. In such a lens forming apparatus, at least one of the first material and the second material including the electron beam curable material or the thermosetting material is cured by at least one of the electron beam irradiation mechanism and the heating mechanism, so that a lens mold is obtained. And a lens can be formed easily and reliably. In particular, by having at least one of a material supply mechanism, an electron beam irradiation mechanism, and a heating mechanism in the same apparatus, it is possible to efficiently perform the steps from application or filling of materials to curing, and to operate continuously. Since it is possible, the tact time can be shortened.

  In a preferred embodiment of the present invention, the stage transmits an electron beam, and the electron beam irradiation mechanism is disposed on the opposite side of the surface of the substrate forming the lens mold. In such a lens forming apparatus, since the electron beam irradiation mechanism is disposed on the surface of the substrate opposite to the lens mold forming surface, the size of the apparatus can be further reduced. Further, since it is not necessary to move the stage to the electron beam irradiation mechanism, the tact time can be shortened.

  According to a preferred embodiment of the present invention, the stage includes a light shielding pattern for controlling the amount of electron beam irradiation. In such a lens forming apparatus, a specific distribution state of the electron beam irradiation is created by blocking the electron beam irradiated from the back side of the substrate by a light shielding pattern such as a dot pattern or a line pattern formed on the stage. The mold can be easily controlled to a concave shape.

  In a preferred embodiment of the present invention, the electron beam irradiation mechanism comprises at least one of an infrared irradiation lamp and an ultraviolet irradiation lamp. In such a lens forming apparatus, it is possible to select a light-shielding portion and a non-light-shielding portion with respect to a portion where a lens is to be formed, and a distribution of curing conditions can be easily created.

  In a preferred embodiment of the present invention, the heating mechanism comprises at least one of a hot plate, a rod type heater, and a plate type heater. In such a lens forming apparatus, the heating region can be heated uniformly, and undried and non-uniform thermosetting can be prevented.

  In a preferred embodiment of the present invention, a gap adjusting mechanism for adjusting a gap between the electron beam irradiation mechanism or the heating mechanism and the substrate is further provided. In this lens forming apparatus, by adjusting the gap between the electron beam irradiation mechanism or the heating mechanism and the substrate, it is possible to change the shape of the lens mold that becomes the target lens shape template. Further, by changing the irradiation region, it is possible to irradiate a large area at a time, so that the tact time can be shortened.

  In a preferred embodiment of the present invention, the first material supply mechanism and the second material supply mechanism comprise at least one of an ink jet mechanism and a dispenser mechanism. In such a lens forming apparatus, it is possible to drop a minute amount of material by using an ink jet mechanism or a dispenser mechanism, and it is possible to form a micro lens of a minute size.

Embodiment 1 of the Invention
An embodiment according to the present invention will be described as follows. First, a lens forming apparatus for carrying out the lens forming method of the present invention will be described below.

  FIG. 1 is a schematic perspective view showing a lens forming apparatus for carrying out the lens forming method of the present invention. The lens forming apparatus according to the present embodiment includes a translucent substrate 11 that forms a lens, a stage 12 on which the substrate 11 is placed and held, and an X axis direction and a Y axis that are orthogonal to each other in a horizontal plane. XY direction drive unit 13a as a horizontal movement mechanism that moves in a direction (see the arrow in FIG. 1), θ rotation drive unit 13b as a horizontal rotation mechanism that rotates the stage 12 in a horizontal plane, and a lens mold forming material on the substrate 11 A first material supply mechanism 14a for applying a curable light-transmitting first material in a drop shape, and a second material supply mechanism 14b for filling the substrate 11 with a curable light-transmitting second material as a lens forming material in a drop shape. And comprising.

  The lens forming apparatus further includes a Z-axis direction drive unit 15 that moves the material supply mechanisms 14a and 14b in the Z-axis direction perpendicular to the horizontal plane (see the arrow in FIG. 1), and an electron beam irradiation mechanism unit 16a or a heating mechanism 16b. And a gap adjusting mechanism 17. The gap adjusting mechanism 17 is for adjusting the gap between the substrate 11 and the electron beam irradiation mechanism 16a or the heating mechanism 16b.

  In the present embodiment, an ink jet method is used as the material supply mechanisms 14a and 14b. Each of the first material supply mechanism 14a and the second material supply mechanism 14b in FIG. 1 is an ink jet head and is installed independently. The electron beam irradiation mechanism 16a is configured such that an infrared irradiation lamp or an ultraviolet irradiation lamp is appropriately replaced depending on the application. The heating mechanism 16b is configured to replace and use a hot plate, a rod type heater, and a plate type heater according to the application. The stage 12 can hold the substrate 11 in a fixed state by evacuating the substrate 11 when the substrate 11 is placed (not shown).

  The lens forming apparatus includes an XY direction driving unit 13a, a θ rotation driving unit 13b, a first material supply mechanism 14a, a second material supply mechanism 14b, a Z-axis direction driving unit 15, an electron beam irradiation mechanism 16a, and a heating mechanism 16b. And a device control unit 18 for performing drive control of the gap adjusting mechanism 17 and the like. The XY direction drive unit 13a, the θ rotation drive unit 13b, the first material supply mechanism 14a, the second material supply mechanism 14b, the Z-axis direction drive unit 15, the electron beam irradiation mechanism 16a, the heating mechanism 16b, and the gap adjustment mechanism 17 are respectively The device control unit 18 is connected by a signal cable (not shown), and the device control unit 18 performs drive control of the XY direction drive unit 13a to the gap adjusting mechanism 17.

  In the present embodiment, the first material supply mechanism 14a and the second material supply mechanism 14b employ an inkjet system. That is, the lens forming apparatus includes a supply tube (not shown) for supplying a liquid material to the inkjet head and a tank (not shown) filled with the liquid material, and the inkjet head and the tank are connected by the supply tube. Yes.

  Next, an outline of a method for forming a lens on the substrate 11 by the lens forming apparatus will be described with reference to FIG. First, a curable translucent first material 19a, which is a lens mold forming material, is applied dropwise to the prepared substrate 11, and the central axis orthogonal to the substrate 11 is set as in the second embodiment to be described later. A concave lens mold 19b is formed. Thereafter, the lens material 19b is filled with the second material 20a dropwise and cured to form the lens 20b.

  Specifically, first, the substrate 11 on which a lens is formed is placed on the stage 12. In this embodiment, a glass substrate is used as the substrate 11. Next, the apparatus control unit 18 controls the XY direction driving unit 13a and the θ rotation driving unit 13b to move the stage 12 to the target position. At this time, the target position is determined so that the portion where the lens is formed is below the first material supply mechanism 14a. That is, by moving and rotating the stage 12, it is possible to determine the lens formation position from an arbitrary location on the substrate 11.

  Next, the first material 19a is applied dropwise to the substrate 11 using the first material supply mechanism 14a to form an application part. Subsequently, the first material 19a of the application part is cured to form the lens mold 19b. At this time, when the first material 19a contains a solvent or a thermosetting material, the stage 12 is controlled to move to the heating region of the heating mechanism 16b and heated to dry the first material 19a. Then, the lens mold 19b is formed.

  On the other hand, when the first material 19a contains an electron beam curable material, the stage 12 is controlled to be moved to the electron beam irradiation region of the electron beam irradiation mechanism 16a, and electrons having a wavelength at which the electron beam curable material is cured. The first material 19a is cured by irradiating a line to form the lens mold 19b.

  Next, the stage 12 is moved again, and the second material 20a is dropped into the concave lens mold 19b formed of the first material 19a by using the second material supply mechanism 14b. After filling the second material 20a, the stage 12 is moved again to the electron beam irradiation region of the electron beam irradiation mechanism 16a or to the heating region of the heating mechanism 16b, the second material 20a is cured, and the desired lens 20b is formed. Form.

  Here, when the second material 20a contains a solvent or a thermosetting material, the second material 20a is dried or cured by the heating mechanism 16b. When the second material 20a contains an ultraviolet curable resin, the second material 20a is cured by irradiating the electron beam with the electron beam irradiation mechanism 16b.

  Thus, the lens 20b is formed by filling the lens mold 19b formed by applying the first material 19a on the substrate 11 with the second material 20a as the lens forming material and curing it.

  Furthermore, the curing conditions can be changed by adjusting the gap (distance) between the substrate 11 and the electron beam irradiation mechanism 16a or the heating mechanism 16b by the gap adjusting mechanism 17.

  In the present embodiment, the gap adjusting mechanism 17 is provided in the electron beam irradiation mechanism 16a or the heating mechanism 16b. However, the gap adjusting mechanism 17 may be a mechanism provided in another part such as the stage 12 side.

  Thus, by forming a lens using the present invention, the lens shape can be controlled to an arbitrary shape without deteriorating lens characteristics.

  Here, a specific example of the lens forming method will be described below. In the present embodiment, a high-pressure mercury ultraviolet irradiation lamp is used as the electron beam irradiation mechanism 16a. Further, a rod-type heater was used as the heating mechanism 16b, and was installed above the substrate (glass substrate, refractive index 1.46) 11. As the first material 19a, an ink in which a thermosetting resin (JN7217 manufactured by JSR Corporation, refractive index 1.40) was dispersed in a solvent was prepared. Further, as the second material 20a, a UV ink of radical polymerization type ultraviolet curable resin (SD2407 manufactured by Dainippon Ink and Refractive Index 1.474) was used. At this time, the ultraviolet irradiation lamp was arranged by the gap adjusting mechanism 17 so that the gap with the substrate 11 was 2.5 cm. Similarly, the gap between the rod heater and the substrate 11 was 1.0 cm.

  Next, the substrate 11 was placed on the stage 12, and the first material 19 a was applied dropwise onto the portion of the substrate 11 where the lens was to be formed by the inkjet method in the present embodiment. After that, the apparatus control unit 18 controls the XY direction drive unit 13a and the θ rotation drive unit 13b to move the stage 12 so that the region (application unit) where the first material 19a is applied is directly below the rod heater. I let you. The time required from the placement of the first material 19a on the substrate 11 to the movement of the stage 12 to the above position is about 15 seconds.

  After the movement of the stage 12 was completed, the solvent of the first material 19a was dried and thermally cured by a rod heater. The temperature range of the surface of the substrate 11 heated by the rod-type heater was set to 50 ° C. to 150 ° C., and heating was performed for 10 minutes to form the lens mold 19b.

  Table 1 shows the shape and flatness of the lens mold 19b obtained by this method.

  Further, FIG. 3A shows the convex shape of the lens mold, and FIG. 3B shows the concave shape of the lens mold. The concave center portion 24 and the concave outer peripheral portion 25 will be described with reference to FIG. The concave center portion 24 is near the center portion of the circle of the contact surface with the substrate 11 and indicates a recessed portion in the concave shape. The concave outer peripheral portion 25 is in the vicinity of the outer peripheral portion of the circle of the contact surface with the substrate 11 and indicates a raised portion in the concave shape.

  When heated at 50 ° C., the shape of the lens mold 19b is a convex shape and is not described in Table 1. When heated at 70 ° C. to 150 ° C., the lens mold 19b had a concave shape. At this time, the film thickness of the concave outer peripheral portion 25 and the film thickness of the concave central portion 24 when the average film thickness was 100% were measured.

  As can be seen from Table 1, the higher the heating temperature, the more conspicuous the concave shape, and the greater the difference in film thickness between the film thickness of the concave outer peripheral portion 25 and the film thickness of the concave central portion 24. This is because the drying speed is different between the concave outer peripheral portion 25 and the concave central portion 24, so that a drying speed distribution is generated and the drying of the concave outer peripheral portion 25 proceeds faster than the concave central portion 24. It was found that the lens mold 19b having an arbitrary concave shape can be formed by changing the heating conditions in this way.

  Next, the stage 12 is moved so that the lens mold 19b is positioned directly below the second material supply mechanism 14b, and the concave material center portion 24 of the concave lens mold 19b is filled with the second material 20a dropwise. did. After filling, the stage 12 was moved to place the lens forming portion in the irradiation region of the ultraviolet irradiation lamp, and cured by performing ultraviolet irradiation for 2 minutes to form the lens 20b.

  It was confirmed that the shape of the lens 20b formed in this way was a lens shape molded using the concave shape of the lens mold 19b as a template. Further, the surface of the lens 20b was smooth, and no deterioration in lens performance was observed. From these, it is possible to control the shape of the lens mold 19b to an arbitrary concave shape by controlling the heating condition of the first material 19a, and it is optional by filling the second material 20a in the lens mold 19b. It has been found that the lens 20b having the shape can be formed. Furthermore, it was found that the lens 20b is formed in the concave center portion of the concave shape of the lens mold 19b, and the lens can be formed with high positional accuracy.

  As described above, by forming a lens using the present invention, it is possible to form a lens having an arbitrary shape without performing a base treatment of a substrate accompanying a design change of the lens. In addition, it is not necessary to measure the contact angle of the lens forming material in advance and select a lens forming material having an appropriate contact angle, and the development time can be shortened.

  In the present embodiment, a rod-type heater is used as the heating mechanism 16b. However, it has been found that the same effect can be obtained by using another heating mechanism such as a hot plate, a plate-type heater, or an infrared irradiation lamp. Moreover, although the high pressure mercury ultraviolet irradiation lamp was used as the electron beam irradiation mechanism 16a, it was confirmed that other lamps may be used as long as the mechanism can irradiate ultraviolet rays. Furthermore, although the first material supply mechanism 14a and the second material supply mechanism 14b are of the ink jet system, it has been confirmed that the same effect can be obtained even if the dispenser system is used.

[Embodiment 2 of the Invention]
Another embodiment according to the present invention will be described as follows. In the present embodiment, as the first material 19a, a UV ink of a radical polymerization type ultraviolet curable resin (JM5010, refractive index 1.41 manufactured by JSR) having a composition different from that of the second material of the first embodiment is used. In addition, as the second material 20a, a UV ink of a radical polymerization type ultraviolet curable resin (SD2407 manufactured by Dainippon Ink, Inc., refractive index 1.474) having the same composition as the second material of Embodiment 1 was used. As the substrate 11, a glass substrate (refractive index: 1.46) was used. Next, a lens forming method for forming the lens mold 19b by applying the first material 19a to the substrate 11 will be described.

  Since the configuration of the lens forming apparatus and the lens forming method are the same as those in the first embodiment, detailed description thereof is omitted. In the present embodiment, as the electron beam irradiation mechanism 16a, an ultraviolet irradiation lamp built in the stage 12 and two types of ultraviolet irradiation lamps installed above the substrate 11 and facing the ultraviolet irradiation lamp are provided. Using.

  FIG. 4 shows a schematic plan view of the stage 12 incorporating the ultraviolet irradiation lamp used in the present embodiment. FIG. 5 is a sectional view taken along the line A-A ′ of FIG. 4. An electron beam irradiation mechanism (ultraviolet irradiation lamp) 16a for irradiating an electron beam is disposed on the back side of the stage 12 on which the substrate 11 is placed. Further, a diffusion plate 21 for diffusing ultraviolet rays is disposed between the stage 12 and the electron beam irradiation mechanism 16a, and a light shielding pattern 22 is disposed on the back surface of the stage 12.

  In the present embodiment, a dot shape pattern as shown in FIG. Further, the entire region of the substrate 11 can be uniformly irradiated with ultraviolet rays by the diffusion plate 21. Furthermore, the distance between the substrate 11 and the electron beam irradiation mechanism 16a can be adjusted by the gap adjusting mechanism 17 provided in the stage 12. In the present embodiment, the electron beam irradiation mechanism 16 a can irradiate an electron beam, and the diffusion plate 21 can cure the first material 19 a applied on the substrate 11.

  Next, UV ink of an ultraviolet curable resin as the first material 19 a was applied to a newly prepared glass substrate as the substrate 11. At this time, the substrate 11 was placed so that the dropping application position of the first material 19a, which is the position where the lens is formed, overlaps the light shielding pattern 22. Next, ultraviolet rays were irradiated by an ultraviolet irradiation lamp (electron beam irradiation mechanism 16a) arranged on the lower side of the stage 12. At this time, the irradiation distance, which is the distance between the ultraviolet irradiation lamp and the stage 12, was 2.5 cm, and irradiation was performed for 2 minutes to form the lens mold 19b. As the light shielding pattern 22, a dot pattern having a radius of 5 μm to 30 μm was used. The diameter of the cross section in contact with the substrate 11 of the lens mold 19b formed in this way is about 60 μm.

  Table 2 shows the shape and flatness of the lens mold 19b formed under these conditions. The film thicknesses of the concave central portion 24 and the concave outer peripheral portion 25 in Table 2 are values calculated with the average film thickness before curing as 100%.

  From Table 2, it was found that the larger the dot-shaped diameter of the light-shielding pattern 22 is, the more the lens mold 19b has a concave shape with a smaller film thickness at the central portion and a larger film thickness at the outer peripheral portion.

  The process of forming the concave lens mold 19b at this time will be described with reference to FIGS. 6 (a), 6 (b), and 6 (c). In addition, the shape shown with the continuous line in FIG.6 (c) is the shape of the 1st material 19a before hardening, and the shape shown with a dotted line is the shape of the lens type | mold 19b after hardening. As can be seen from FIGS. 6A and 6B, as the diameter of the dot shape of the light shielding pattern 22 increases, the light shielding region 23 shielded by the dot pattern increases. For this reason, the 1st material 19a contained in the light-shielding area | region 23 is maintaining fluidity, without hardening | curing by ultraviolet irradiation. However, the first material 19a not included in the light-shielding region 23 is cured and contracted by irradiation with ultraviolet rays.

  As a result, the fluid first material 19a included in the light shielding region 23 is pulled outward, and the lens mold 19b has a concave shape with a depressed center. On the other hand, since the first material 19a in the region not included in the light shielding region 23 has been cured, the viscosity is increased and the fluidity is lowered, and the first material 19a included in the light shielding region 23 is outside due to the contraction. Even if it is attracted, it does not spread outward. Then, the first material 19a in the light shielding region 23 flows so as to be deposited upward (in the Z-axis direction), and is cured by being irradiated with an electron beam by exiting the light shielding region 23.

  In this way, the concave lens mold 19b can be formed by making the irradiation amount to the central portion of the first material 19a containing the electron beam curable material smaller than the irradiation amount to the outer peripheral portion.

  Next, the stage 12 is moved under the second material supply mechanism 14b, the second material 20a is filled into the concave lens mold 19b in a drop shape, and the second material is irradiated with ultraviolet rays from an ultraviolet irradiation lamp. 20a was cured to form a lens 20b. The lens 20b thus formed had a smooth surface and had a lens shape using the shape of the lens mold 19b as a template. Further, the concave lens mold 19b could be formed with high positional accuracy around the concave central portion 24.

  As described above, by forming a lens using the present invention, a lens having an arbitrary shape can be formed without performing a substrate surface treatment associated with a change in lens design. In particular, by irradiating ultraviolet rays from the surface opposite to the surface on which the first material 19a is applied on the substrate 11 by the stage 12 on which the light shielding pattern 22 is formed and the electron beam irradiation mechanism 16a built in the stage 12, The shape of the lens mold 19b can be easily formed into an arbitrary concave shape.

  It was found that the lens 20b can be formed with high positional accuracy by filling the second material 20a in a drop shape at the center position of the concave center portion 24 of the concave lens mold 19b formed in this way. At this time, it is not necessary to incorporate the electron beam irradiation mechanism 16a in the stage 12, and the same result was obtained by irradiating the electron beam from the surface opposite to the surface coated with the first material 19a.

  That is, even if the substrate 11 is removed from the stage 12 once, the electron beam is irradiated from the surface opposite to the application surface of the first material 19a, and it is placed on the stage 12 again, the concave lens mold 19a is similarly formed. It was found that the lens 20b having excellent lens characteristics can be formed with high positional accuracy by applying the second material 20a to the lens mold 19b thus formed.

Embodiment 3 of the Invention
The following will describe still another embodiment according to the present invention. In the present embodiment, the same radical polymerization type ultraviolet curable resin (JM5010, refractive index 1.41 made by JSR) as the first material 19a of the second embodiment is used. A lens forming method for forming a lens mold 19b formed by applying the first material 19a as a template will be described. Also in the present embodiment, the second material 20a is the same as that of the first embodiment (SD2407 manufactured by Dainippon Ink, Inc., refractive index 1.474).

  Since the configuration of each device and the lens forming method are the same as those in the first embodiment, description thereof is omitted. In the present embodiment, an ultraviolet irradiation lamp is used as the electron beam irradiation mechanism 16a, and the light shielding pattern 22 which is a dot pattern is installed on the ultraviolet irradiation lamp. At this time, the dot pattern was circular and the diameter was 5-30 micrometers. The distance between the ultraviolet irradiation lamp and the substrate surface was 1.0 cm.

  The ultraviolet rays irradiated by the ultraviolet irradiation lamp can be distributed in the irradiation amount by the light shielding pattern 22. FIG. 7 is a schematic explanatory diagram of the irradiation amount distribution by the ultraviolet irradiation lamp used in the present embodiment.

  First, also in this embodiment, a glass substrate is used as the substrate 11. That is, a new glass substrate (refractive index 1.46) was prepared as the substrate 11 and placed on the stage 12. The stage 12 on which the substrate 11 is placed is moved, and the first material 19a is applied to the substrate 11 dropwise by the first material supply mechanism 14a. Next, ultraviolet rays are irradiated by an ultraviolet irradiation lamp, and a light shielding region 23 is formed in the central portion of the first material in the first material 19a by the light shielding pattern 22 formed in the ultraviolet irradiation lamp.

  The fluidity is not lost because the first material 19a in the region included in the light-shielding region 23 is not cured, but the first material 19a not included in the light-shielding region 23 begins to cure and contracts due to ultraviolet irradiation. For this reason, the first material 19a having fluidity contained in the light shielding region 23 is pulled outside by being contracted without being contained in the light shielding region 23, and thus the cured lens die 19b has a concave shape.

  Table 3 shows the shape and flatness of the lens mold 19b thus formed.

  Under either condition, it was found that the concave lens mold 19b can be formed by increasing the amount of ultraviolet irradiation to the outer peripheral portion rather than the amount of ultraviolet irradiation to the central portion of the applied first material 19a.

  Next, the stage 12 was moved below the second material supply mechanism 14b, and the second material 20a was dropped into the concave center portion 24 of the concave lens mold 19b by the second material supply mechanism 14b. Thereafter, the second material 20a was cured by irradiating ultraviolet rays to form a lens 20b.

  The lens 20b thus formed has a smooth surface, has a lens shape with the shape of the lens mold 19b as a template, and has a high positional accuracy around the concave center portion of the concave lens mold 19b. Could be formed.

  Thus, it has been found that by forming a lens using the present invention, it is possible to form a lens having an arbitrary shape without performing a substrate surface treatment associated with a lens design change. In particular, the electron beam irradiation mechanism 14a in which the light shielding pattern 22 is formed irradiates ultraviolet rays so that the irradiation amount to the central portion of the applied first material 19a is larger than the irradiation amount to the outer peripheral portion. The shape of 19b can be easily formed into an arbitrary concave shape. It was found that the lens 20b can be formed with high positional accuracy by filling the second material 20a with the concave center portion 24 of the concave lens mold 19b formed in this way as the application position of the second material 20a. .

[Embodiment 4 of the Invention]
The following will describe still another embodiment according to the present invention. The first material 19a and the second material 20a used in the present embodiment are the same as the first material 19a used in the second embodiment (JM5010 manufactured by JSR Corporation, refractive index 1.41) and the second material 20a ( A material obtained by dispersing red, blue, and green pigments in SD2407 manufactured by Dainippon Ink and a refractive index of 1.474) was used. The ratio of the pigment dispersed in the first material 19a and the second material 20a is 10% by volume. The configuration of the apparatus in the present embodiment is the same as that in the third embodiment.

  Also in the present embodiment, the ultraviolet rays irradiated by the ultraviolet irradiation lamp can be distributed in the irradiation amount by the light shielding pattern 22. At this time, the distance between the ultraviolet irradiation lamp and the surface of the substrate 11 was 1.0 cm, and a dot pattern having a diameter of 20 μm was used as the light shielding pattern 22. In the present embodiment, a glass substrate (refractive index: 1.46) on which a lattice-shaped light shielding pattern 28 is formed is used as the substrate 11. The lattice-shaped light shielding pattern 28 used at this time is the pattern shown in FIG.

  First, the substrate 11 on which the lattice-shaped light-shielding pattern 28 is formed is placed on the stage 12, the stage 12 is moved below the first material supply mechanism 14a, and the first material 19a is transferred to the substrate by the first material supply mechanism 14a. 11 was applied dropwise. At this time, the position where the first material 19a is applied will be described with reference to FIG. FIG. 8B is an enlarged view of the grid-like light shielding pattern 28 shown in FIG.

  Application was performed so that the center position of the grid-shaped light-shielding pattern 22 and the center position of the applied first material 19a overlap and do not spread to the adjacent grid. Next, the first material 19a was cured by irradiating ultraviolet rays with an ultraviolet irradiation lamp to form a concave lens mold 19b. Table 4 shows the shape and flatness of the lens mold 19b thus formed.

  From Table 4, it was found that the concave lens mold 19b can be formed by applying the colored first material 19a and increasing the amount of ultraviolet irradiation to the outer peripheral portion rather than the amount of ultraviolet irradiation to the central portion.

  Next, the stage 12 was moved below the second material supply mechanism 14b, and the second material 20a was dropped into the concave center portion 24 of the concave lens mold 19b by the second material supply mechanism 14b. Thereafter, the filled second material 20a was again irradiated with ultraviolet rays with an ultraviolet irradiation lamp to cure the second material 20a, thereby forming a lens 20b.

  The lens thus formed had a smooth surface and a lens shape using the shape of the lens mold 19b as a template. Further, by forming the lens 20b with the concave center portion 24 of the concave lens mold 19b as the dropping filling position of the second material 20a, the lens 20b can be formed with high positional accuracy.

  Thus, it has been found that by forming a lens using the present invention, a colored lens having an arbitrary shape can be formed without subjecting the substrate to a base treatment accompanying a lens design change. Further, it was found that the lens 20b can be formed with high positional accuracy by using the concave center portion 24 of the concave lens mold 19b as the dropping filling position of the second material 20a.

  Next, as shown in FIG. 9, the substrate 11 on which the red colored lens 20b is formed is removed from the stage 12 out of the lenses 20b formed in this way, and parallel light 27 is incident using a surface light source. It was. At this time, the parallel light 27 emitted from the surface light source was incident in the direction from the lens 20b toward the substrate 11. For comparison, a lens formed by applying a second material 20a to the substrate 11 and irradiating it with ultraviolet rays by the inkjet method which is also a conventional technique, and a color filter substrate prepared by the conventional photolithography method. Similarly, the parallel light 27 was also incident on the.

  As shown in FIG. 9, the color filter substrate has a colored portion 26 and a grid-like light shielding pattern 28, and the colored portion 26 becomes an effective pixel region 30 that transmits parallel light 27 from a surface light source. It has been found that when the parallel light 27 is transmitted through the color filter substrate, the light is shielded by the lattice-shaped light shielding pattern 28 and the luminance is lowered. The amount of light decreased as the area occupied by the lattice-shaped light shielding pattern 28 increased. For this reason, a surface light source with a large output is required to increase the luminance.

  This distance is substantially the same as the distance obtained by adding the thickness of the lens mold 19b formed according to the present invention and the thickness of the glass substrate 11 on which the lattice-shaped light shielding pattern 28 is formed. Further, the size of the lattice-shaped light shielding pattern 28 is one third of the radius of the convex lens, and one end thereof is arranged so as to overlap the end portion of the convex lens. That is, all the parallel light 27 incident on the convex lens is condensed on the effective pixel region 30.

  When a colored lens is formed by applying only the second material 20a to the substrate 11 in a drop shape by the inkjet method, the parallel light 27 incident on the lattice-shaped light shielding pattern 28 is condensed on the effective pixel region 30 by the lens. Therefore, it was possible to prevent a decrease in luminance in the effective pixel region 30. However, color unevenness occurred in the effective pixel region 30 due to different distances through which light passes through the lens.

  FIG. 10 shows color unevenness in a convex lens formed by applying only the second material 20a to the substrate 11 by the inkjet method, and color unevenness in the lens 20b formed by the present embodiment.

  The triangle mark shown in FIG. 10 is the color unevenness when the parallel light 27 is transmitted through the substrate 11 formed by applying the second material 20a by the ink jet method, and the circle mark is the lens 20b formed by the present invention. This is the color unevenness when the parallel light 27 is transmitted. The vertical axis represents the color purity distribution at each position when the color purity at the center position of the effective pixel region 30, that is, the position where the light transmitted through the center position of the lens is irradiated onto the substrate 11 is 100%. The axis represents the position where the color purity was measured.

  The position where the color purity is measured will be described with reference to FIG. The measurement position in the B-B ′ sectional view shown in FIG. 11 is the horizontal axis in FIG. 10, and the color purity at each position is the vertical axis in FIG. 10. The convex lens has the thickest center part of the lens. For this reason, the distance that the parallel light 27 passes through the center of the convex lens is the longest, and the color purity is the darkest. On the other hand, at the end of the convex lens, since the distance of the parallel light 27 passing through the convex lens is the shortest, the color purity is the thinnest. As a result, the color distribution of the lens is generated concentrically from the center of the effective pixel region 30, and color unevenness occurs. That is, when such a convex lens is used as, for example, a color filter with a brightness enhancement function, color unevenness occurs, and the display performance of the formed panel is degraded.

  On the other hand, even when the colored lens 20b is formed according to the present embodiment, since the parallel light 27 is condensed on the effective pixel region 30 by the lens 20b, it has been found that luminance reduction due to the lattice-shaped light shielding pattern 28 can be prevented. . Further, as shown by the circles in FIG. 10, it was found that a colored lens having excellent lens characteristics with small color unevenness can be formed.

  The parallel light 27 incident on the end of the lens 20b passes through the lens mold 19b. At this time, there is a difference in the distance that the light passes through the lens 20b. However, the parallel light 27 incident on the end of the lens 20b due to the condensing by the lens 20b is different from the parallel light 27 incident on the central portion of the lens 20b. In comparison, the distance transmitted through the lens mold 19b becomes longer. That is, the shorter the distance that passes through the lens 20b, the longer the distance that passes through the lens mold 19b.

  In the present invention, since the lens mold 19b is also colored with the same density as the lens 20b, the colored lens mold 19b corrects the difference in the distance of the light passing through the lens 20b to thereby obtain an effective pixel region. It was found that 30 color unevenness can be reduced. The same result was obtained when the first material 19a and the second material 20a in which a blue or green pigment was dispersed were used.

  Thus, it has been found that when a panel is formed using the colored lens formed according to the present invention, the incident light is condensed and the luminance is increased. Furthermore, it has been found that color unevenness can be reduced by correcting the difference in the light passing distance generated when light passes through the colored lens by the difference in the distance passing through the lens mold 19b colored in the same color. When such a lens is used as a color filter with a brightness enhancement function, the display performance of the panel increases.

  In this embodiment, the radical polymerization type UV curable resin UV ink is used. However, other materials may be used as long as they contain an electron beam curable material or a thermosetting material. As long as it is an ultraviolet curable resin, a radical polymerizable material, a cationic polymerizable material, or a mixture thereof may be used. Such curable materials include curable monomers or curable oligomers, polymerization initiators, and the like. In addition to the electron beam curable material and the thermosetting material, other components such as a solvent, a pigment, and a dye may be included.

  In the present embodiment, a dot pattern is used as the light shielding pattern 22, but any material or shape may be used as long as it has a function of shielding light having a wavelength required for curing. Further, the light shielding pattern 22 may not be directly formed on the stage 12 or the electron beam irradiation mechanism 14a but may be arranged separately. You may form directly on the board | substrate 11 which forms the lens 20b. Further, the diffusion plate 21 may not be provided. Furthermore, the light shielding pattern 22 does not need to completely shield the irradiation light, and may be any pattern that forms a distribution in the irradiation amount.

  In the present embodiment, a glass substrate is used as the substrate 11 on which the lens 20b is formed, but any substrate may be used. A plastic substrate or a film substrate may be used. Further, the surface of the substrate 11 may be uneven or a pattern may be formed. Further, when the electron beam is irradiated from the surface opposite to the coating side, a substrate that does not completely block the electron beam to be irradiated may be used.

  In this embodiment, the ink jet method is used. However, a bubble jet (registered trademark) type using an electrothermal transducer as an energy generating element or a piezo jet type using a piezoelectric element may be used. The first material supply mechanism 14a and the second material supply mechanism 14b do not have to be the same mechanism.

  It is sufficient that the refractive index n1 of the lens mold 19b and the refractive index n2 of the lens 20b satisfy the relationship n1 <n2. That is, when light enters the lens mold 19a having a low refractive index from the lens 20b having a high refractive index, the light can be refracted and condensed away from the normal line of the interface.

  In the present embodiment, the first material 19a and the second material 20a are colorless, red, green, or blue, but may be any color. Not only pigments but also dyes may be used. Moreover, although the pigment density | concentration disperse | distributed to the 1st material 19a and the 2nd material 20a was made into the same density | concentration, this may not be the same density | concentration. Depending on the refractive index of the lens 20b, the size of the lattice-shaped light-shielding pattern 28, the thickness of the glass substrate on which the lattice-shaped light-shielding pattern 28 is formed, etc., it can be changed according to the shape of the lens mold 19b.

  Furthermore, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.

  As described above, according to the lens forming method of the present invention, the first material 19a is applied to the substrate 11 to form the concave lens mold 19b, and the lens mold 19b is filled with the second material 20a. Thus, the lens 20b having an arbitrary shape can be formed. Furthermore, the lens 20b can be formed with high positional accuracy around the recessed portion of the concave central portion 24 of the lens mold 19b.

  According to the present invention, a lens having excellent lens characteristics can be formed without causing deterioration of lens characteristics due to loss of smoothness of the lens surface when an absorption layer is formed in advance as seen in the prior art. . Also, with the lens forming method according to the present invention, a lens having excellent characteristics can be formed at an arbitrary location with high positional accuracy.

  In the case of forming a colored lens, the lens mold 19b is colored in the same color as the lens 20b, thereby correcting the difference in the distance that incident light passes through the lens 20b and reducing color unevenness. it can.

  In addition, according to the lens forming method of the present invention, it is not necessary to perform a base treatment on the substrate in advance when changing the lens shape, so that the tact time can be shortened and the cost can be reduced. In addition, it is not necessary to change the lens forming material by measuring the contact angle between the lens forming material and the substrate in advance so as to obtain an arbitrary lens shape, so that the development period can be shortened. .

1 is a schematic perspective view showing a lens forming apparatus according to Embodiment 1 of the present invention. It is a schematic explanatory drawing of the lens formation method which concerns on Embodiment 1 of this invention. (A) It is a schematic sectional drawing of the convex shape of a lens. (B) It is a schematic sectional drawing of the concave shape of a lens. It is a top view of the stage which built in the ultraviolet irradiation lamp based on Embodiment 2 of this invention. FIG. 5 is a cross-sectional view taken along line A-A ′ of FIG. 4. (A) It is sectional drawing which shows the light-shielding area | region by the light-shielding pattern which concerns on Embodiment 2 of this invention. (B) It is sectional drawing which shows the light-shielding area | region by the light-shielding pattern which concerns on Embodiment 2 of this invention. (C) It is explanatory drawing which shows the fluidity | liquidity of the 1st material contained in the light-shielding area | region which concerns on Embodiment 2 of this invention. It is explanatory drawing which shows the light-shielding area | region by the ultraviolet irradiation lamp which concerns on Embodiment 3 of this invention, and a light-shielding pattern. (A) It is a top view which shows the board | substrate which has the grid | lattice-like light shielding pattern which concerns on Embodiment 4 of this invention. (B) It is explanatory drawing showing the position which apply | coats 1st material with respect to the lattice-shaped light shielding pattern. (A) It is explanatory drawing showing the distance which the parallel light which injected into the color filter substrate passes the inside of a lens. (B) It is explanatory drawing showing the distance of the parallel light which passes the inside of the convex lens formed by apply | coating a 2nd material to a board | substrate by the inkjet method. (C) It is explanatory drawing showing the distance of the parallel light which passes the inside of the lens formed by this invention. It is a figure showing the color purity distribution of the effective pixel area | region which generate | occur | produces when parallel light injects into a colored lens. It is explanatory drawing explaining the cross section which measured the color purity distribution in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Board | substrate 12 Stage 13a XY direction drive part 13b (theta) rotation drive part 14a 1st material supply mechanism 14b 2nd material supply mechanism 15 Z-axis direction drive part 16a Electron beam irradiation mechanism 16b Heating mechanism 17 Gap adjustment mechanism 18 Apparatus control unit 19a 1st 1 material 19b lens type 20a second material 20b lens 21 diffuser plate 22 light shielding pattern 23 light shielding area 24 concave center part 25 concave outer peripheral part 26 colored part 27 parallel light 28 grid light shielding pattern 29 focal position 30 effective pixel area

Claims (15)

  A curable translucent first material is applied to the surface of the translucent substrate to form an application portion, and the application portion is cured while controlling the curing conditions to form a concave lens mold. A lens forming method of forming a lens by filling a curable translucent second material and curing it.   The lens forming method according to claim 1, wherein the first material contains an electron beam curable material, and the lens mold is formed by curing the first material by electron beam irradiation.   The lens forming method according to claim 2, wherein the lens mold is formed by making the irradiation amount to the outer peripheral portion of the application portion larger than the irradiation amount to the central portion of the application portion.   4. The lens forming method according to claim 2, wherein the electron beam irradiation is performed from a surface opposite to the surface of the substrate on which the coating portion is formed.   The lens forming method according to claim 1, wherein the first material contains a thermosetting material, and the lens mold is formed by curing the first material by heating at a predetermined temperature or higher.   A stage for holding a translucent substrate, a first material supply mechanism for supplying a curable translucent first material for forming a lens mold on the surface of the substrate, and a lens formed on the surface of the substrate A lens forming apparatus comprising: a second material supply mechanism for supplying a curable translucent second material for forming a lens on a mold.   The lens forming apparatus according to claim 6, further comprising a horizontal movement mechanism for moving the stage in a horizontal plane and a horizontal rotation mechanism for rotating the stage in the horizontal plane.   The lens forming apparatus according to claim 6 or 7, further comprising at least one of an electron beam irradiation mechanism and a heating mechanism for curing at least one of the first material and the second material.   The lens forming apparatus according to claim 8, wherein the stage transmits an electron beam, and the electron beam irradiation mechanism is disposed on a side opposite to a surface of the substrate forming the lens mold.   The lens forming apparatus according to claim 9, wherein the stage includes a light shielding pattern for controlling an electron beam irradiation amount.   The lens forming apparatus according to any one of claims 8 to 10, wherein the electron beam irradiation mechanism includes at least one of an infrared irradiation lamp and an ultraviolet irradiation lamp.   The lens forming apparatus according to claim 8, wherein the heating mechanism includes at least one of a hot plate, a rod type heater, and a plate type heater.   The lens forming apparatus according to any one of claims 8 to 12, further comprising a gap adjusting mechanism for adjusting a gap between the electron beam irradiation mechanism or the heating mechanism and the substrate.   The lens forming apparatus according to claim 6, wherein the first material supply mechanism and the second material supply mechanism include at least one of an ink jet mechanism and a dispenser mechanism.   The lens forming method according to claim 1, wherein the refractive index n1 of the lens mold and the refractive index n2 of the lens satisfy a relationship of n1 <n2.

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